Electronic component accommodation packages such as SMD (Surface Mount Device) packages (surface mount type device packages) are conventionally known which are used to hermetically seal electronic components such as SAW filters (Surface Acoustic Wave filters), quartz resonators and oscillators that are used for noise elimination of mobile phones and the like. This type of electronic component accommodation package includes an electronic component accommodation member (case) to which an electronic component is mounted, and a hermetic sealing cap that hermetically seals the electronic component accommodation member. This hermetic sealing cap is heated to melt a solder layer, and thus joined to the electronic component accommodation member. For this reason, the hermetic sealing cap is configured to have high solder wettability. Accordingly, when the hermetic sealing cap is used to provide hermetic sealing, the solder layer may wetly spread on a sealing surface of the hermetic sealing cap. If the solder layer thus wetly spreads on the sealing surface of the hermetic sealing cap, solder between the hermetic sealing cap and the electronic component accommodation member may be insufficient, which in turn causes a disadvantage that hermeticity decreases. In addition, if the solder layer wetly spreads inward on the sealing surface of the hermetic sealing cap, this may cause a disadvantage that the solder layer comes in contact with bonding wire that connects the electronic component and the electronic component accommodation member. Additionally, in the case where an electronic component such as a quartz resonator and an oscillator is accommodated, if the solder layer wetly spreads inward on the sealing surface of the hermetic sealing cap, the solder that wetly spreads inward may splatter and adhere onto the electronic component such as a quartz resonator and an oscillator. Such adhesion or the like may cause a disadvantage that the frequency characteristic of the electronic component varies or deteriorates. Hence, a hermetic sealing cap is proposed until now which suppresses that the solder layer wetly spreads inward on a sealing surface of the hermetic sealing cap when the hermetic sealing cap is used to provide hermetic sealing. This type of hermetic sealing cap is disclosed in Japanese Patent Laying-Open No. HEI 4-96256, for example.
The aforementioned Japanese Patent Laying-Open No. HEI 4-96256 discloses a metallic hermetic sealing cover (hermetic sealing cap) that has a sealing surface that is provided with an electronic component accommodation member joined thereon and is plated with Ni, and an area inside the area to which the electronic component accommodation member is joined and is oxidized by using laser. In this metallic hermetic sealing cover, since the area inside the area to which the electronic component accommodation member is joined is oxidized by using laser, the solder wettability of the oxidized area in the metallic hermetic sealing cover decreases. Accordingly, it is possible to suppress that the solder layer wetly spreads inward on the sealing surface of the metallic hermetic sealing cover, when the metallic hermetic sealing cover is used to hermetically seal the electronic component accommodation member. In addition, in the aforementioned Japanese Patent Laying-Open No. HEI 4-96256, in order to suppress that an area of the metallic hermetic sealing cover to which the electronic component accommodation member is joined is oxidized, the area of the metallic hermetic sealing cover to which the electronic component accommodation member is joined is masked by using an aluminum plate when the area of the metallic hermetic sealing cover inside the area to which the electronic component accommodation member is joined is oxidized by using laser.
However, since, in the aforementioned Japanese Patent Laying-Open No. HEI 4-96256, in order to suppress that the area of the metallic hermetic sealing cover to which the electronic component accommodation member is joined is oxidized, the area of the metallic hermetic sealing cover to which the electronic component accommodation member is joined is masked by using an aluminum plate when the area of the metallic hermetic sealing cover inside the area to which the electronic component accommodation member is joined is oxidized by using laser, there is a disadvantage that requires a mask forming stage and a mask removing stage. For this reason, there is a problem that makes a production process complicated. In addition, in the case where the area of the metallic hermetic sealing cover to which the electronic component accommodation member is joined is not masked by using an aluminum plate for suppression of oxidation, since Ni plating of the area of the metallic hermetic sealing cover to which the electronic component accommodation member is joined is likely oxidized, there is a disadvantage that the joining characteristic by the solder decreases caused by solder wettability reduction in the area of the metallic hermetic sealing cover to which the electronic component accommodation member is joined.